I currently have several designs running well on ADAU1466-300. Assuming the data and program memory usage is below the limit of ADAU1462-300, can I use the ADAU1466-300 generated code and load directly onto ADAU1462-300 without any changes? Or does the code need to be re-compiled for ADAU1462-300?
No changes at all is the answer. The only thing to keep in mind is to watch the memory usage. The Compiler Output reports are setup for the larger memory sizes so it will not report the usage totals correctly.
If you would like to change it you can drop in a second IC into the design. Then go to the schematic and select all. Then change them all to IC2. It will bark at you and say some cells were not changed, that would be the input and output cells. So then you delete and reinsert those cells from the library. Then you can go back to the configuration and delete IC1. That is one way to do it but you should nit have to do this.
I routinely run Sigma300 code on a Sigma350 and Sigma350 code on a Sigma300. It works as long as you do not try to use features or memory that are not on the older or smaller part. The cores are the same and we designed them to be backwards compatible.
I notice after replacing the ADAU1466 IC with ADAU1462 IC using your method above, the signal lines connecting the In/Out ports are greenish color, while the pre-existing signal lines are all yellow. Does this indicate anything that I need to worry about?
Not a problem. This is because you can have multiple DSPs in a single project which is really handy. However, you cannot connect a cell from DSP 1 to DSP 2 because it is physically impossible. So SigmaStudio will use different colored wires to differentiate between signals in different DSPs. So since you changed it to a different IC number the color changed.
Oh! and I should mention that I have seen some bugs where the pre-existing wires are not the correct color. It still should compile properly.